Adhesive coated paper



iii

Patented Aug. 1, 1939 UNITED STATES PATENT "OFFICE am mn ADHESIVE COATED PAPER- I No Drawing. Application April 22, 1933, Serial .No. 85,859

a" Claims.

This invention relates to new and useful improvements in adhesive coated paper, cloth or other material and pertainsmore particularly to a moisture protected adhesive coating for summed tape and the like.

it has been proposed heretofore to protect adhesive coated material from the deleterious absorption of moisture from a humid atmosphere by the application of a protective soap layer. The object of the soap layer has been to prevent the penetration of the adhesive material by sufficient atmospheric moisture to render the material excessivelyi, sticky. While such coatings of soap have met'iwith a certain degree of success in some applications. it has been iound that materials so coated are too slippery for certain'uses. This is particularly true where the coated material is to be wound into rolls, particularly narrow rolls such as used in connection with telegraph printers. .The slippery coating tends to cause difliculty in the slitting machines which slit the paper into strips and wind the strips into rolls, since the successive layers of paper tend to slip sidew'l'se. with respect to one another. This difficulty is also presented in the handling of the finished rolls of coated paper, since on accountof the excessive slipperiness of the soap coating the center of the rolls easily falls out, making a tangled mass, unless great care is used. Ordinary soap films are also likely to discolor paper tape when stored for any length of time.

It is an object of the present invention to provide an adhesive coating for use in connection with paper, cloth or the like, which will be strong ly resistant to deleterious absorption of atmos pheric moisture while at the same time being sumciently tacky so that paper or other material coated therewith may be wound into rolls which may be easily handled and at the same time safely stored.

In accordance with my invention the paper, cloth or the like is first passed through any suitable gumming machine and thereby coated with a layer of any suitable gum or adhesive. A thin coating of a substance to be described below is sprayed, dusted or otherwise applied to the adhesive while the tape passes through the drying mechanism "of the'gumming machine so that as r the coating dries the protective film will adhere firmly thereto. Alternatively the film may be applied in a separate operation.

In accordance with my invention the coating material is primarily an aliphatic amine salt which may be made by mixing an aliphatic amine with a fatty acid. Suitable aliphatic amines are ethylene diamine, propylene diamine. triethanoi amine, morpholine, while the fatty acids may he of a saturated nature such as palmiticor steai'lc,

or of an unsaturated character such as oleic or linoleic. The mixture of the aliphatic amine and 5 iatty acid is preferably made in stoichiometric proportions but it may be desirable to have the final mixture at. some definite hydrogen ion concentration other than at pH'l. This may be accomplished by the addition of an alkali or acid 10 as may be necessary. For example, small proportions of sodium or potassium hydroxide or hydrochloric or sulphuric acid may he used for this purpose. Other alkalis or acids may also be used.

A successful coating material has been made from triethanolamine and palmitic acid in approximately stoichiometric proportions and diluted with water to form approximately a 10% iii solution. A coating of this material sprayed to 20.

the extent of one-half pound, dry weight, per 500 sheets of paper 17" 22", over a glue film of 6.5 pounds gave a satisfactory result by affording ample protection to the under glue coating upon exposure to humid weather conditions, while 25 at the same time presenting a surface which was not too slippery for successful use of the material under most conditions.

A still less slippery film which is entirely adequate to protect an adhesive coating against 30 humid atmospheric conditions may be obtained through the use of an emulsion formed by proper treatment of anoil, fat or wax, e. g. mineral oil, glyceryl palmitate, camauba wax with. an aliphatic amine salt. The mineral oil may be 5 U. S. P., automobile cylinder oil or the like. Other fats may also be used such as glyceryl stearate, glyceryl oleate or mixtures of these. In place of carnauba wax or in mixture therewith other waxes may be used e. g. paramn wax, beeswax, or 40 the like. An emulsion with an aliphatic amine salt similar to the one above mentioned made with paraflin oil as the oil phase was found to be entirely successful, when made as follows in the Oleic acid (7.3 grams) was added to 2 grams of paraflin oil and the mixture stirred until homogenous. Triethanolamine was then added and stirred until a clear viscous solution re- 55 and stirred until a clear solutionv was again obtained. Hot water (250 grams) was then slowly added with rapid stirring until a uniform emulsion was obtained.

In place of a portion of the mineral 011 an organic plastic such as chlorinated dlphenyl (Aroclor"), rubber, rubber latex, aromatic sulfonamide plastic (Santolite MS) etc. may be used ,and by adding a greater or lesser percentage of this material the tackiness of the coating can be controlled without materially reducing its resistance to atmospheric moisture or ability to take up water deliberately applied, for example, by a hand tape moistener, to wet the adhesive. By this means any difilculty in slitting and winding paper into rolls and handling rolls so made, which result from an excessively slippery film, may be controlled.

The following are two successful formulas using proportions of the above mentioned organic plastics as modifying substance to control tackiness.

These coating emulsions may be prepared generally as described in connection with the formula first given, the organic plastic being initially mixed with the oil constituent.

While I have described particular embodiments of my invention for purposes of illustration it should be understood that various modifications.

and adaptations thereof occurring to one skilled in the art may be made within the spirit of the invention as set forth in the appended claims.

What I claim is:

1. As an article of manufacture adhesive sheet material comprising a base of sheet material, a layer of hygroscopic water-soluble adhesive on said base, and superposed upon said layer a protective coating primarily consisting of analiphatic amine salt of a fatty acid.

2 As an article of manufacture adhesive sheet material comprising a base of sheet material, a layer of hygroscopic water-soluble adhesive on said base, and superposed upon said layer a protective coating primarily consisting of a substance from the group consisting of oils, fats and 9, 167,71 1 suited. The remaining parafiin oil was then added waxes. emulsified with an aliphatic amine salt of a fatty acid. i

3. As an article of manufacture adhesive sheet material comprising a base of sheet material, a

layer of hygroscopic water-soluble adhesive off 5 said base, and superposed upon said layer a protective coating primarily consisting of a substance from the group consisting of oils, fats and waxes, together with an organic plastic emulsified with an aliphatic amine salt of a fatty acid, said 1 organic plastic being from the group consisting of chlorinated diphenyl, rubber, rubber latex, aromatic sulfonamide plastic.

4. As an article of manufacture adhesive sheet material comprising a base of sheet material, a u

layer of hygroscopic water-soluble adhesive on said base, and superposed upon said layer a protective coating primarily consisting of a neutral mixture of an aliphatic amine and fatty acid containing an admixture of a substance from" the group consisting of oils, fats and waxes.

5. As an article of manufacture adhesive sheet material comprising a base of sheet material, a layer of hygroscopic water-soluble adhesive on said base, and superposed upon said layer a protective coating primarily consisting of a neutral mixture of an aliphatic amine and fatty acid containing an admixture of a substance from the group consisting of oils, fats and waxes, and'an organic plastic from the group consisting of chlorinated diphenyl, rubber, rubber latex, aromatic sulfonamide plastic.

6. As an article of manufacture adhesive sheet material comprising a base of sheet material, a layer of' hygroscopic water-soluble adhesive on said base, and superposed upon said layer a protective coating primarily consisting of an aqueous emulsion of the following constituents in approximately the proportions given: 10 grams mineral oil, 7.3 grams oleic acid, 2.8 grams triethanolamine.

7. As an article of manufacture adhesive sheet material comprising a base of sheet material, a layer of hygroscopic water-soluble adhesive on said base, and superposed upon said layer a protective coating primarily consisting of a triethanolamine salt of a fatty acid.

8. As an article of manufacture a roll ofaadhesive sheet material comprising a base of sheet material, a layer of hygroscopic water-soluble adhesive, and superposed upon said layer a protective coating essentially consisting of an aliphatic amine salt of a fattyacid and an admixture of a tackiness-promoting agent from the organic plastic group consisting of chlorinated diphenyl, rubber, rubber latex, aromatic sulfonamide plastic in such proportion as to render said coating sufficiently tacky to prevent slippi'ngof said sheet material in said roll.

HAROLD R. DALTON. 

